Couldn't find a SIMPLE version of how to make this work. This method doesn't use any inertia, but the very basics of how this works will get your project working.
1) Create a sprite.
2) Give it 8 direction control, set it to up and down only.
3) Give it LookAt behavior, enable it to 'create the camera'
4) Make a global variable called TouchStartY
5) See image:
The concept is simple. Store the first touch, compare it with where the user is touching at a later time. For this example I just used every 0.001 seconds.
If you slow this down you could get inertia scrolling pretty easily.
This gives a pretty good "SOLID SCROLL" effect.